Image processing apparatuses and image processing methods have been proposed to combine multiple images and generate one high-resolution image. One known technique selects one scene from a moving image taken with a digital video camera and generates a higher-resolution still image (having a higher pixel density) than an original frame image of the selected scene. This prior art technique selects one frame image among (n+1) consecutive frame images as a reference image, calculates motion vectors of the other n frame images (subject images) relative to the selected reference image, and combines the (n+1) frame images based on the calculated motion vectors to generate one still image (see, for example, Japanese Patent Laying-Open Gazette No. 2000-244851). This image processing technique enhances the picture quality and increases the sharpness of the composite image, compared with the simple conversion of the resolution of one frame image.